//
//Filename: maxCamera.cs
//
// original: http://www.unifycommunity.com/wiki/index.php?title=MouseOrbitZoom
//
// --01-18-2010 - create temporary target, if none supplied at start

using UnityEngine;
using System.Collections;


[AddComponentMenu("Camera-Control/3dsMax Camera Style")]
public class MaxCamera : MonoBehaviour
{
		
	
		void Start ()
		{
				Init ();
		}
		void OnEnable ()
		{
				Init ();
		}
	
		public void Init ()
		{
				//If there is no target, create a temporary target at 'distance' from the cameras current viewpoint
				if (!target) {
						GameObject go = new GameObject ("Cam Target");
						go.transform.position = transform.position + (transform.forward * distance);
						target = go.transform;
				}
		
				distance = Vector3.Distance (transform.position, target.position);
				currentDistance = distance;
				desiredDistance = distance;
		
				//be sure to grab the current rotations as starting points.
				position = transform.position;
				rotation = transform.rotation;
				currentRotation = transform.rotation;
				desiredRotation = transform.rotation;
		
				xDeg = Vector3.Angle (Vector3.right, transform.right);
				yDeg = Vector3.Angle (Vector3.up, transform.up);
		}
	
		/*
     * Camera logic on LateUpdate to only update after all character movement logic has been handled. 
     */
		void LateUpdate ()
		{
				// If Control and Alt and Middle button? ZOOM!
				if (Input.GetMouseButton (2) && Input.GetKey (KeyCode.LeftAlt) && Input.GetKey (KeyCode.LeftControl)) {
						desiredDistance -= Input.GetAxis ("Mouse Y") * Time.deltaTime * zoomRate * 0.125f * Mathf.Abs (desiredDistance);
				}
		// If middle mouse and left alt are selected? ORBIT
		else if (Input.GetMouseButton (2) && Input.GetKey (KeyCode.LeftAlt)) {
						xDeg += Input.GetAxis ("Mouse X") * xSpeed * 0.02f;
						yDeg -= Input.GetAxis ("Mouse Y") * ySpeed * 0.02f;
			
						////////OrbitAngle
			
						//Clamp the vertical axis for the orbit
						yDeg = ClampAngle (yDeg, yMinLimit, yMaxLimit);
						// set camera rotation 
						desiredRotation = Quaternion.Euler (yDeg, xDeg, 0);
						currentRotation = transform.rotation;
			
						rotation = Quaternion.Lerp (currentRotation, desiredRotation, Time.deltaTime * zoomDampening);
						transform.rotation = rotation;
				}
		// otherwise if middle mouse is selected, we pan by way of transforming the target in screenspace
		else if (Input.GetMouseButton (2)) {
						//grab the rotation of the camera so we can move in a psuedo local XY space
						target.rotation = transform.rotation;
						target.Translate (Vector3.right * -Input.GetAxis ("Mouse X") * panSpeed);
						target.Translate (transform.up * -Input.GetAxis ("Mouse Y") * panSpeed, Space.World);
				}
		
				////////Orbit Position
		
				// affect the desired Zoom distance if we roll the scrollwheel
				desiredDistance -= Input.GetAxis ("Mouse ScrollWheel") * Time.deltaTime * zoomRate * Mathf.Abs (desiredDistance);
				//clamp the zoom min/max
				desiredDistance = Mathf.Clamp (desiredDistance, minDistance, maxDistance);
				// For smoothing of the zoom, lerp distance
				currentDistance = Mathf.Lerp (currentDistance, desiredDistance, Time.deltaTime * zoomDampening);
		
				// calculate position based on the new currentDistance 
				position = target.position - (rotation * Vector3.forward * currentDistance + targetOffset);
				transform.position = position;
		}
	
		private static float ClampAngle (float angle, float min, float max)
		{
				if (angle < -360)
						angle += 360;
				if (angle > 360)
						angle -= 360;
				return Mathf.Clamp (angle, min, max);
		}

		public Transform target;
		public Vector3 targetOffset;
		public float distance = 5.0f;
		public float maxDistance = 20;
		public float minDistance = .6f;
		public float xSpeed = 200.0f;
		public float ySpeed = 200.0f;
		public int yMinLimit = -80;
		public int yMaxLimit = 80;
		public int zoomRate = 40;
		public float panSpeed = 0.3f;
		public float zoomDampening = 5.0f;
	
		private float xDeg = 0.0f;
		private float yDeg = 0.0f;
		private float currentDistance;
		private float desiredDistance;
		private Quaternion currentRotation;
		private Quaternion desiredRotation;
		private Quaternion rotation;
		private Vector3 position;
}